Vehicle and control method for vehicle

ABSTRACT

An ECU executes a program including: a step of setting a threshold β as a shutdown threshold when, during a power supply operation, a duration of a power supply stoppage exceeds a first time; a step of stopping an operation of an engine or prohibiting the engine from operating; and a step of executing system shutdown processing when an SOC of a storage apparatus falls to or below the shutdown threshold or the duration of the power supply stoppage exceeds a second time.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a divisional application based on U.S. patent application Ser.No. 14/409,605, filed Dec. 19, 2014, which is a national phaseapplication based on the PCT International Patent Application No.PCT/IB2013/001754 filed Aug. 12, 2013, claiming priority to JapanesePatent Application No. 2012-184176 filed Aug. 23, 2012, the entirecontents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a technique for supplying power from a powergeneration apparatus that uses an engine as a power source or power froma storage apparatus to a power supply subject outside a vehicle.

2. Description of Related Art

Japanese Patent Application Publication No. 2000-234539 (JP-2000-234539A), for example, discloses a control apparatus for a hybrid vehicle thatperforms power generation using a generator by controlling an enginerotation speed such that an engine is driven at or above a predeterminedcatalyst activation temperature in a case where power is supplied to theoutside of the vehicle from an external outlet.

SUMMARY OF THE INVENTION

In the hybrid vehicle disclosed in JP-2000-234539 A, the engine may bedriven in order to maintain the catalyst activation temperature evenwhen an amount of power used by a power supply destination is small or adevice at the power supply destination is temporarily stopped during anintermittent operation, and as a result, fuel may be consumedwastefully.

The invention provides a vehicle and a control method for the vehiclewith which an engine is controlled appropriately in accordance with anoperating condition of a power supply destination.

A vehicle according to a first aspect of the invention includes: anengine; a storage apparatus capable of supplying power to a power supplysubject outside the vehicle; a power generation apparatus capable ofsupplying power to the power supply subject using the engine as a powersource; and a control apparatus configured to operate the engine inaccordance with a condition of the vehicle during a power supplyoperation in which power is supplied to the power supply subject from atleast one of the power generation apparatus and the storage apparatus.The control apparatus is configured to suppress an operation of theengine when a power supply remains continuously smaller than apredetermined value. The power supply is the power supplied to the powersupply subject during the power supply operation.

In the vehicle, the control apparatus may be configured to stop theoperation of the engine or prohibit the engine from operating when aduration of a condition in which the power supply is smaller than thepredetermined value exceeds a first time.

In the vehicle, the control apparatus may, be configured to stop asystem of the vehicle that is activated during the power supplyoperation when the duration exceeds a second time, and the second timemay be longer than the first time.

In the vehicle, the control apparatus may be configured to stop a systemof the vehicle that is activated during the power supply operation whena remaining capacity of the storage apparatus falls below a threshold,and the threshold employed when the power supply remains continuouslysmaller than the predetermined value may be equal to or larger than thethreshold employed when the power supply is larger than thepredetermined value or when the duration is equal to or shorter than thefirst time.

In the vehicle, the control apparatus may be configured to permit theengine to operate when the power supply is equal to or larger than thepredetermined value or when the duration is equal to or shorter than thefirst time.

In the vehicle, in a case where the power supply is equal to or largerthan the predetermined value or a case where the duration is equal to orshorter than the first time, the control apparatus may be configured topermit the engine to operate when a remaining capacity of the storageapparatus falls below a threshold.

In the vehicle, in a case where the power supply is equal to or largerthan the predetermined value or a case where the duration is equal to orshorter than the first time, the control apparatus may be configured topermit the engine to operate when a catalyst temperature of the enginefalls below a threshold.

A second aspect of the invention relates to a control method for avehicle. The vehicle includes an engine, a storage apparatus, and apower generation apparatus. The control method includes: operating theengine in accordance with a condition of the vehicle during a powersupply operation in which power is supplied to a power supply subjectoutside the vehicle from at least one of the power generation apparatusand the storage apparatus, the power generation apparatus being capableof supplying power to the power supply subject using an engine as apower source, and the storage apparatus being capable of supplying powerto the power supply subject; and suppressing an operation of the enginewhen a power supply remains continuously smaller than a predeterminedvalue, the power supply being the power supplied to the power supplysubject during the power supply operation.

According to the invention, the operation of the engine is suppressedwhen the power supply remains continuously smaller than thepredetermined value during the power supply operation. Therefore, theoperation of the engine is suppressed even when an operation of theengine is requested due to a reduction in the catalyst temperature orthe like, for example. As a result, wasteful fuel consumption can beavoided. It is therefore possible to provide a vehicle and a controlmethod for the vehicle with which an engine is controlled appropriatelyin accordance with operating conditions of a power supply destination.

BRIEF DESCRIPTION OF THE DRAWINGS

Features, advantages, and technical and industrial significance ofexemplary embodiments of the invention will be described below withreference to the accompanying drawings, in which like numerals denotelike elements, and wherein:

FIG. 1 is a view showing a power supply connector attached to a vehiclewith an electric device connected thereto;

FIG. 2 is a side view of the power supply connector;

FIG. 3 is an enlarged view showing a part of the power supply connectorinto which a plug of the electric device is inserted;

FIG. 4 is an overall block diagram of the vehicle according to thisembodiment;

FIG. 5 is a view showing a first modified example of the power supplyconnector;

FIG. 6 is a view showing a second modified example of the power supplyconnector;

FIG. 7 is a block diagram showing functions of an electronic controlunit (ECU) installed in the vehicle according to this embodiment; and

FIG. 8 is a flowchart showing a control structure of a program executedby the ECU installed in the vehicle according to this embodiment.

DETAILED DESCRIPTION OF EMBODIMENTS

An embodiment of the invention will be described below with reference tothe drawings. In the following description, identical components havebeen allocated identical reference symbols. Names and functions thereofare also identical. Accordingly, detailed description of thesecomponents will not be repeated.

As shown in FIG. 1, a vehicle 100 is provided with an inlet 220. One endof a connector used exclusively for supplying power (to be referred tohereafter as a power supply connector) 600 that can be attached to anddetached from the vehicle 100 is attached to the inlet 220. A socket 610that can be connected to a plug 710 connected to a household electricdevice 700 (to be referred to simply as the electric device 700hereafter) such as a rice cooker is provided on another end of the powersupply connector 600.

When the power supply connector 600 is connected to the inlet 220 andthe plug 710 of the electric device 700 is connected to the power supplyconnector 600, a power supply operation is executed in the vehicle 100.By executing the power supply operation, power from the vehicle 100 issupplied to the electric device 700 serving as a power supply subjectvia the inlet 220, the power supply connector 600, and the plug 710.

Hence, as a result of the power supply operation, the electric device700 such as a rice cooker connected to the power supply connector 600can be operated by power stored in a storage apparatus or the like ofthe vehicle 100 or power generated in a power generation apparatus, tobe described below, which uses an engine as a power source.

The power supply connector 600 is provided with an operating member 615.The power supply connector 600 can be detached from the inlet 220 bypressing the operating member 615.

FIG. 2 is a side view of the power supply connector 600. In FIG. 2, thepower supply connector 600 includes a main body portion 633 providedwith a connecting portion 631, and a main body portion 634 provided withthe socket 610.

The connecting portion 631 that is connected to the inlet 220 of thevehicle 100, and a pawl portion 635 provided to catch on a recess formedin the inlet 220 when the power supply connector 600 is attached to theinlet 220 are provided on one end of the main body portion 633. The mainbody portion 633 includes a rod-shaped member that extends in ahorizontal direction. The operating member 615 for releasing anengagement between the pawl portion 635 and the inlet 220 is provided onan upper portion of the main body portion 633.

The connecting portion 631 has a shape that corresponds to the inlet 220so that the connecting portion 631 can be fitted to the inlet 220.Further, by pressing the operating member 615, the catch between thepawl portion 635 and the recess formed in the inlet 220 is released, andas a result, the inlet 220 and the connecting portion 631 can bedisconnected. In other words, a user can detach the power supplyconnector 600 from the vehicle 100 by pressing the operating member 615.

The main body portion 634 includes a rod-shaped member that extends inan inclined direction oriented downward from a horizontal plane. Notethat the main body portion 634 may include a rod-shaped member thatextends in a vertical direction. One end of the main body portion 634 isconnected to the main body portion 633. The main body portion 633 andthe main body portion 634 may be formed integrally or separately.

The socket 610 is provided on another end of the main body portion 634.A projecting portion 641 that projects in an extension direction of themain body portion 634 is formed on an upper side of a surface on whichthe socket 610 is provided. By forming the projecting portion 641,rainwater and the like can be prevented from adhering to the socket 610when the power supply connector 600 is used outdoors in the rain.

The power supply connector 600 is provided with a cover 642 forprotecting the surface provided with the socket 610 when the powersupply connector 600 is not in use. As shown in FIG. 3, a rotary portionof the cover 642 is provided below the surface provided with the socket610. The cover 642 is formed to be capable of rotating in a rotationdirection 684 using the rotary portion as a rotary center. When an outeredge part of the cover 642 is rotated until the cover 642 contacts theprojecting portion 641, the socket 610 is covered, and thus protected,by the cover 642.

Further, when the cover 642 of the power supply connector 600 is open,the socket 610 is exposed. A terminal hole to which the plug 710 of theelectric device 700 can be connected is formed in the socket 610. Thesocket 610 has a similar shape to a socket disposed in a house or thelike.

FIG. 4 is an overall block diagram of the vehicle 100 according to thisembodiment. Referring to FIG. 4, the vehicle 100 includes a storageapparatus 110, a system main relay (SMR) 115, a power control unit (PCU)120 serving as a driving apparatus, motor/generators 130, 135, a powertransmission gear 140, a drive wheel 150, an engine 160 constituted byan internal combustion engine, a power conversion apparatus 200, adirect current (DC) current sensor 202, an alternating current (AC)current sensor 204, a charging relay (also referred to hereafter as aCHR) 210, the inlet 220, and an ECU 300 serving as a control apparatus.

The storage apparatus 110 is a chargeable/dischargeable power storageelement. For example, the storage apparatus 110 is constituted by asecondary battery such as a lithium ion battery, a nickel hydrogenbattery, or a lead storage battery, or a storage element such as anelectric double layer capacitor.

The storage apparatus 110 is connected to the PCU 120 via a power linePL1 and a ground line NL1. The storage apparatus 110 supplies power forgenerating a driving force of the vehicle 100 to the PCU 120. Further,the storage apparatus 110 stores power generated by the motor/generators130, 135. An output of the storage apparatus 110 is approximately 200 V,for example.

The storage apparatus 110 includes a voltage sensor, a current sensor,and a temperature sensor, none of which are shown in the drawings, and avoltage VB, a current IB, and a battery temperature TB of the storageapparatus 110, which are detected respectively by these sensors, areoutput to the ECU 300.

One relay included in the SMR 115 is connected to a positive electrodeterminal of the storage apparatus 110 and the power line PL1 connectedto the PCU 120, while another relay is connected to a negative electrodeterminal of the storage apparatus 110 and the ground line NL1. The SMR115 switches between supplying and cutting off power between the storageapparatus 110 and the PCU 120 on the basis of a control signal SE1 fromthe ECU 300.

The PCU 120 includes a converter that performs voltage conversionbetween the storage apparatus 110 and an inverter, to be describedbelow, on the basis of a control signal PWC from the ECU 300, and theinverter that converts DC power supplied from the converter into ACpower on the basis of control signals PWI1, PWI2 from the ECU 300 anddrives the respective motor/generators 130, 135.

The motor/generators 130, 135 are AC rotating electric machines, forexample permanent magnet synchronous motors including a rotor having anembedded permanent magnet.

An output torque of the motor/generators 130, 135 is transmitted to thedrive wheel 150 via the power transmission gear 140, which includes areduction gear and a power distribution mechanism, to cause the vehicle100 to travel. When a regenerative braking operation is underway in thevehicle 100, the motor/generators 130, 135 are capable of generatingpower using a rotary force of the drive wheel 150. This generated poweris converted by the PCU 120 into charging power for the storageapparatus 110.

Further, the motor/generators 130, 135 are joined to the engine 160 viathe power transmission gear 140. The motor/generators 130, 135 and theengine 160 are operated cooperatively by the ECU 300 so that a requiredvehicle driving force is generated. Furthermore, the motor/generators130, 135 can generate power using a rotation of the engine 160, and thestorage apparatus 110 can be charged using the resulting generatedpower.

Note that in this embodiment, the motor/generator 135 is usedexclusively as a motor for driving the drive wheel 150, while themotor/generator 130 is used exclusively as a power generation apparatusdriven by the engine 160.

In the example shown in FIG. 1, two motor/generators are provided, butthe number of motor/generators is not limited to two, and a singlemotor/generator or more than two motor/generators may be providedinstead.

The vehicle 100 includes the power conversion apparatus 200, thecharging relay 210 (to be referred to hereafter as the CHR 210), and theinlet 220 serving as a connecting portion as a configuration forcharging the storage apparatus 110 using power from an external powersupply 500, or supplying the power of the storage apparatus 110 or powergenerated by an MG1 to an external load.

For example, when the power supply connector 600 is connected to theinlet 220, a power supply operation is performed in the vehicle 100.When a charging connector (not shown) connected to an external powersupply (a commercial power supply, for example) on the outside of thevehicle 100 is connected to the inlet 220, on the other hand, a chargingoperation is performed in the vehicle 100.

The power conversion apparatus 200 is connected to the inlet 220 viapower lines ACL1, ACL2. Further, the power conversion apparatus 200 isconnected to the storage apparatus 110 by a power line PL2 and a groundline NL2 via the CHR 210.

The power conversion apparatus 200 is controlled by a control signal PWDfrom the ECU 300 to convert AC power supplied from the inlet 220 into DCpower for the storage apparatus 110, and to convert the DC power of thestorage apparatus 110 or DC power generated by the motor/generators 130,135 and converted by the PCU 120 into AC power and supply the AC powerto an electric device on the outside of the vehicle 100.

The power conversion apparatus 200 may be a single apparatus capable ofbidirectional power conversion for charging and supplying power, or mayinclude individual apparatuses used respectively for charging andsupplying power.

The CHR 210 is controlled by a control signal SE2 from the ECU 300 toswitch between supplying and cutting off power between the powerconversion apparatus 200 and the storage apparatus 110.

The DC current sensor 202 is provided on the ground line NL2 to detect aDC Idc of the ground line NL2. The DC current sensor 202 transmits asignal indicating the detected DC Idc to the ECU 300.

The AC current sensor 204 is provided on the ground line ACL2 to detectan AC Iac of the ground line ACL2. The AC current sensor 204 transmits asignal indicating the detected AC Iac to the ECU 300.

The ECU 300 includes a central processing unit (CPU) 310, a resistorcircuit 320, an input buffer 340, and a storage device (not shown). TheECU 300 receives signals input from the respective sensors and so on,outputs control signals to the respective devices, and controls thestorage apparatus 110 and the respective devices of the vehicle 100.Note that this control is not limited to software processing, and may beperformed using dedicated hardware (electronic circuits).

The ECU 300 calculates a state of charge (SOC) of the storage apparatus110 on the basis of detection values of the voltage VB, the current IB,and the battery temperature TB from the storage apparatus 110.

The ECU 300 estimates a catalyst temperature on the basis of conditions(for example, an intake air amount, a rotation speed, a throttleopening, a fuel injection amount, an ignition timing, an intake airtemperature, and so on) of the engine 160. The ECU 300 may detect thecatalyst temperature using a temperature sensor used in a catalyst, orthe ECU 300 may estimate the catalyst temperature using a temperaturesensor provided in the vicinity of the catalyst.

Note that in FIG. 4, a single control apparatus is provided as the ECU300, but instead, an individual control apparatus may be provided foreach function or each controlled device so that, for example, a controlapparatus is provided for the PCU 120, a control apparatus is providedfor the storage apparatus 110, and so on.

When the power supply connector 600 is connected to the inlet 220, thevehicle 100 side power lines ACL1, ACL2 and the socket 610 areelectrically connected via a power transmission unit 606.

The power supply connector 600 further includes resistors R30, R31 and aswitch SW30 constituting a connection detection circuit 611. When thepower supply connector 600 is connected to the inlet 220, the resistorsR30, R31 are connected in series between a connection signal line L3 anda ground line L2.

The switch SW30 is connected in parallel with the resistor R31. When thepower supply connector 600 is fitted securely into the inlet 220, acontact of the switch SW30 is closed. When the power supply connector600 is disconnected from the inlet 220 and when the power supplyconnector 600 and the inlet 220 are not securely fitted, the contact ofthe switch SW30 is open. The contact of the switch SW30 is also openedby operating the operating member 615.

When the power supply connector 600 is connected to the inlet 220, theCPU 310 is capable of determining a connection condition and a fittingcondition of the power supply connector 600 using a combined resistancedefined by a combination of resistors R10, R15, R30, R31.

Note that a resistance value of the connection detection circuit in thepower supply connector 600 is set at a different value to a resistancevalue of a connection detection circuit provided in the chargingconnector used in the charging operation. Accordingly, a potential of aconnection signal PISW generated when the power supply connector 600 isfitted takes a different value to the potential of the connection signalPISW generated when the charging connector is fitted. As a result, theCPU 310 can determine which of the charging connector and the powersupply connector 600 is connected to the inlet 220 on the basis of thepotential of the connection signal PISW.

After acknowledging on the basis of the potential of the connectionsignal PISW that the power supply connector 600 is connected, the CPU310 closes the CHR 210 and controls the power conversion apparatus 200to perform the power supply operation, whereby the power of the storageapparatus 110 is supplied to the external electric device 700.

The CPU 310 also drives the engine 160 to cause the motor/generator 130to generate power, and supplies the generated power to the electricdevice 700.

The resistance values of the connection detection circuits providedrespectively in the power supply connector 600 and the chargingconnector used in the charging operation are set to be different fromeach other. As a result, the CPU 310 can determine which of the chargingconnector and the power supply connector 600 is connected to the inlet220.

The resistor circuit 320 is connected in series between a control pilotline L1 over which a pilot signal CPLT used in the charging operation iscommunicated, and a vehicle earth 360. The resistor circuit 320 is acircuit for manipulating a potential of the pilot signal CPLT from thevehicle 100 side.

A configuration in which the plug 710 of the external electric device700 is connected to the power supply connector 600 was described above,but as shown in FIG. 5, a power supply cable 400A capable oftransmitting power from a power supply connector 410A via a cable mayalso be used.

In the power supply cable 400A shown in FIG. 5, a plug 420A has a maletype plug shape. By forming the plug 420A of the power supply cable 400Ain this shape, power can be supplied to electric devices in a house 800from the vehicle 100 when a power cut occurs in the house 800, forexample, by connecting the plug 420A to an outlet 810 of the house 800.In this case, the house 800 serves as the power supply subject.Moreover, power can be supplied to the individual electric device 700using an adaptor 720 capable of connecting the plug 420A of the powersupply cable 400A and the plug 710 of the electric device 700. Note thatthe plug 420A may also have a female type plug shape.

Alternatively, as shown in FIG. 6, a cable that is capable of switchingbetween charging the storage apparatus 110 using an external powersupply and supplying the power of the storage apparatus 110 or the powergenerated by the motor/generator 130 to the external electric device maybe used.

A charging/power supply cable 400B shown in FIG. 6 is formed byreplacing the power supply connector 410A of the power supply cable 400Aillustrated in FIG. 5 with a charging/power supply connector 410B.

The charging/power supply connector 410B is provided with a switch 416in addition to the configuration of the power supply connector 410A. Theswitch 416 is used to switch between the charging operation and thepower supply operation, and by switching the switch 416 to “Emergency”,the vehicle 100 is caused to perform the power supply operation to theoutside while driving the engine to generate power. Further, byswitching the switch 416 to “Normal”, the vehicle 100 is caused toperform the charging operation. The switch between the chargingoperation and the power supply operation does not have to be performedmanually, and may be performed by the vehicle 100 or by a power supplydestination or a charging source (the house, for example).

In the vehicle configured as described above, the engine 160 may bedriven in order to maintain the catalyst activation temperature evenwhen an amount of power used by the electric device 700 serving as thepower supply subject is small or the electric device 700 is temporarilystopped during an intermittent operation, and as a result, fuel may beconsumed wastefully.

Hence, in this embodiment, when a power supply supplied to the electricdevice 700 serving as the power supply subject remains continuouslysmaller than a predetermined value during the power supply operation inwhich power is supplied to the electric device 700 from at least one ofthe motor/generator, 130 and the storage apparatus 110, the ECU 300suppresses an operation of the engine 160.

More specifically, when the power supply remains smaller than thepredetermined value continuously for more than a first time during thepower supply operation, the ECU 300 stops the operation of the engine160 or prohibits the engine 160 from operating. For example, in a casewhere the power supply remains smaller than the predetermined valuecontinuously for more than the first time, the ECU 300 stops theoperation of the engine 160 when the engine 160 is operative, andprohibits the engine 160 from operating when the engine 160 is stopped.

Further, when the power supply to the electric device 700 is equal to orlarger than the predetermined value or when the duration of a conditionin which the power supply is smaller than the predetermined value isequal to or shorter than the first time, the ECU 300 permits the engine160 to operate.

For example, in a case where the power supply is equal to or larger thanthe predetermined value during the power supply operation or a casewhere the duration of a condition in which the power supply is smallerthan the predetermined value is equal to or shorter than the first timeduring the power supply operation, the ECU 300 operates the engine 160when the remaining capacity of the storage apparatus 110 falls below athreshold or the catalyst temperature of the engine 160 falls below athreshold.

FIG. 7 is a block diagram showing functions of the ECU 300 installed inthe vehicle 100 according to this embodiment. The ECU 300 includes amode determination unit 382, a power supply determination unit 384, anelapsed time determination unit 386, a threshold setting unit 388, anengine control unit 390, a shutdown determination unit 392, and a systemshutdown processing unit 394.

The mode determination unit 382 determines whether or not a power supplymode is set. For example, the mode determination unit 382 may determinethat the power supply mode is set when the power supply connector 600 isconnected to the inlet 220. A method of determining whether or not thepower supply connector 600 is connected to the inlet 220 was describedabove, and therefore detailed description thereof will not be repeated.

After determining that the power supply mode is set, the modedetermination unit 382 may set a mode determination flag to ON, forexample.

When the mode determination unit 382 determines that the power supplymode is set, the power supply determination unit 384 determines whetheror not the power supply is stopped, or in other words whether or not thepower supply is smaller than a predetermined value.

For example, the power supply determination unit 384 may determine thatthe power supply is stopped when a magnitude of a detection value of theDC Idc detected by the DC current sensor 202 is smaller than a thresholdIdc (0).

Note that the threshold Idc (0) is a value for determining that themagnitude of the detection value of the DC Idc is substantially zero,which is set in consideration of detection errors and the like.

Alternatively, for example, the power supply determination unit 384 maydetermine that the power supply is stopped when a magnitude of aneffective value of the AC Iac detected by the AC current sensor 204 issmaller than a threshold Iac (0). The power supply determination unit384 calculates the magnitude of the effective value using a maximumvalue of a detection value of the AC Iac, for example. The threshold Iac(0) is a value for determining that the magnitude of the effective valueof the AC Iac is substantially zero, which is set in consideration ofdetection errors and the like.

Alternatively, for example, the power supply determination unit 384 maydetermine that the power supply is stopped when a magnitude of thedetection value of the current IB detected by the current sensorprovided in the storage apparatus 110 is smaller than a threshold IB(0). The threshold IB (0) is set at a value at which the power supply tothe electric device 700 can be determined to be smaller than thepredetermined value, taking into consideration an amount of powerconsumed by accessories installed in the vehicle 100, an amount of powerconsumed by switching loss, and so on.

Alternatively, for example, the power supply determination unit 384 maycalculate a reduction in the SOC of the storage apparatus 110 perpredetermined time, and determine that the power supply is stopped whena magnitude ΔSOC of the calculated reduction is smaller than a thresholdΔSOC (0). ΔSOC (0) is a value for determining that the reduction issubstantially zero.

Alternatively, for example, the power supply determination unit 384 maydetermine that the power supply is stopped upon reception from theelectric device 700 side (including the house) of information indicatingthat the electric device 700 is temporarily stopped during anintermittent operation or information indicating the power supply viathe power supply connector, through wireless communication, or byanother method.

The power supply determination unit 384 may determine that the powersupply is stopped when the mode determination flag is ON, and afterdetermining that the power supply is stopped, the power supplydetermination unit 384 may set a stoppage determination flag to ON.

Further, in a case where the power supply determination unit 384determines whether or not the power supply is stopped by receivinginformation from the current sensor provided in the storage apparatus110, information indicating the SOC of the storage apparatus 110, orinformation from the electric device 700 side, the DC current sensor 202and the AC current sensor 204 may be omitted.

The elapsed time determination unit 386 determines whether or not aduration of a power supply stoppage has exceeded a predetermined firsttime. The first time is a threshold for determining whether or not thepower supply remains stopped.

For example, the elapsed time determination unit 386 starts to measurethe elapsed time (the duration of the power supply stoppage) using atimer or the like from the point at which the power supply is determinedto be stopped. When the power supply operation is resumed duringmeasurement of the elapsed time, the elapsed time determination unit 386resets the elapsed time to an initial value, and when the power supplyis subsequently determined to be stopped, the elapsed time determinationunit 386 starts to measure the elapsed time again.

When the measured elapsed time exceeds the first time, the elapsed timedetermination unit 386 may set an elapse determination flag to ON, forexample.

The threshold setting unit 388 sets an SOC threshold (to be referred toas a shutdown threshold hereafter) for executing system shutdownprocessing, to be described below, in accordance with whether or not thepower supply remains stopped.

For example, the threshold setting unit 388 sets a threshold α as theshutdown threshold when the power supply is not stopped or the durationof the power supply stoppage has not exceeded the first time.

When the duration of the power supply stoppage has exceeded the firsttime, on the other hand, the threshold setting unit 388 sets a thresholdβ, for example, as the shutdown threshold. For example, the thresholdsetting unit 388 may set the threshold α as the shutdown threshold whenthe elapse determination flag is OFF and set the threshold β as theshutdown threshold when the elapse determination flag is ON. Note thatthe threshold α takes a smaller value than the threshold β.

The engine control unit 390 controls the engine 160 in accordance withwhether or not the power supply remains stopped. More specifically, theengine control unit 390 permits the engine 160 to operate when the powersupply is not stopped or when the duration of the power supply stoppagehas not exceeded the first time.

For example, in a case where the power supply is not stopped or theduration of the power supply stoppage has not exceeded the first time,the engine control unit 390 operates the engine 160 when the SOC of thestorage apparatus 110 falls below an electric vehicle (EV) threshold.

The EV threshold is a value for determining whether or not to operatethe engine when the power supply is not stopped (i.e. when power supplyis underway), and is a larger value than the threshold β. In otherwords, the EV threshold is a threshold of the SOC of the storageapparatus 110 for determining during the power supply operation whetherto supply the power of the storage apparatus 110 to the power supplysubject or to operate the engine 160 in order to supply power generatedby the motor/generator 130 to the power supply subject in addition to orinstead of the power of the storage apparatus 110.

A value that enables the vehicle 100 to perform EV travel (travel usingthe motor/generator 135 while the engine 160 is stopped) for at least apredetermined distance following cancellation of the power supply mode,for example, is set as the EV threshold.

Note that the engine control unit 390 may operate the engine 160 in acase where the power supply is not stopped or the duration of the powersupply stoppage has not exceeded the first time when the catalysttemperature of the engine 160 is smaller than a threshold, for example.The catalyst temperature threshold is set at a value at which thecatalyst temperature can be determined to be within a catalystactivation temperature range. For example, the catalyst temperaturethreshold may be set at a lower limit value of the catalyst activationtemperature range or a value that is higher than the lower limit valueby a predetermined value.

Further, for example, the engine control unit 390 may permit the engine160 to operate when the elapse determination flag is OFF.

When the duration of the power supply stoppage has exceeded the firsttime, on the other hand, the engine control unit 390 stops the operationof the engine 160 or prohibits the engine 160 from operating, forexample. For example, the engine control unit 390 stops the operation ofthe engine 160 when the engine 160 is operative and prohibits the engine160 from operating when the engine 160, is stopped.

While the operation of the engine 160 is stopped or the engine 160 isprohibited from operating, the engine control unit 390 does not operatethe engine 160 even when the catalyst temperature falls below thethreshold, for example.

Further, for example, the engine control unit 390 may stop the operationof the engine 160 or prohibit the engine 160 from operating when theelapse determination flag is ON.

The shutdown determination unit 392 determines whether or not the SOC ofthe storage apparatus 110 has fallen to or below the shutdown threshold.When the power supply is not stopped or when the duration of the powersupply stoppage does not exceed the first time, the shutdowndetermination unit 392 determines whether or not the SOC of the storageapparatus 110 has fallen to or below the threshold α. For example, theshutdown determination unit 392 may determine whether or not the SOC ofthe storage apparatus 110 has fallen to or below the threshold α whenthe elapse determination flag is OFF.

When the duration of the power supply stoppage exceeds the first time,for example, the shutdown determination unit 392 determines whether ornot the SOC of the storage apparatus 110 has fallen to or below thethreshold β. For example, the shutdown determination unit 392 maydetermine whether or not the SOC of the storage apparatus 110 has fallento or below the threshold β when the elapse determination flag is ON.

After determining that the SOC of the storage apparatus 110 has fallento or below the shutdown threshold, the shutdown determination unit 392may set a shutdown determination flag to ON, for example.

Further, when the SOC of the storage apparatus 110 is larger than theshutdown threshold, for example, the shutdown determination unit 392determines whether or not the duration of the power supply stoppageexceeds a predetermined second time. There are no particular limitationson the second time providing it is longer than the first time.

For example, the shutdown determination unit 392 may set the shutdowndetermination flag to ON when the duration of the power supply stoppageis determined to have exceeded the second time, even in a case where theSOC of the storage apparatus 110 is larger than the shutdown threshold.

The system shutdown processing unit 394 executes the system shutdownprocessing on the basis of a determination result obtained by theshutdown determination unit 392. For example, the system shutdownprocessing unit 394 executes the system shutdown processing when theshutdown determination unit 392 determines that the SOC of the storageapparatus 110 has fallen to or below the shutdown threshold or when theduration of the power supply stoppage is determined to have exceeded thesecond time.

The system shutdown processing unit 394 executes processing for stoppinga system of the vehicle 100 that is activated during the power supplyoperation as the system shutdown processing. For example, the systemshutdown processing unit 394 sets the CHR 210 in a shutdown condition.Note that as long as the system shutdown processing unit 394 can stopthe system of the vehicle 100 that is activated during the power supplyoperation, the system shutdown processing unit 394 is not limited tosetting the CHR 210 in the shutdown condition. For example, the systemshutdown processing unit 394 may control the power conversion apparatus200 to stop the power supply operation.

Further, the system shutdown processing unit 394 may execute the systemshutdown processing when, for example, the shutdown determination flagis ON.

In this embodiment, the mode determination unit 382, the power supplydetermination unit 384, the elapsed time determination unit 386, thethreshold setting unit 388, the engine control unit 390, the shutdowndetermination unit 392, and the system shutdown processing unit 394 allfunction as software that is realized by having the CPU 310 of the ECU300 execute a program stored in the storage device. However, these unitsmay be realized by hardware. Note that the program is recorded on astorage medium and installed in the vehicle.

Referring to FIG. 8, a control structure of the program executed by theECU 300 installed in the vehicle 100 according to this embodiment willnow be described.

In Step (to be abbreviated to S hereafter) 100, the ECU 300 determineswhether or not the power supply mode is set. When it is determined thatthe power supply mode is set (YES in S100), the processing advances toS102. Otherwise (NO in S100), the processing returns to S100.

In S102, the ECU 300 determines whether or not the power supply isstopped. When it is determined that the power supply is stopped (YES inS102), the processing advances to S104. Otherwise (NO in S102), theprocessing advances to S110.

Note that a method of determining whether or not the power supply modeis set and a method of determining whether or not the power supply isstopped were described above, and therefore detailed description thereofwill not be repeated.

In S104, the ECU 300 determines whether or not the duration of the powersupply stoppage exceeds the first time. When it is determined that theduration of the power supply stoppage exceeds the first time (YES inS104), the processing advances to S106. Otherwise (NO in S104), theprocessing advances to S110.

In S106, the ECU 300 sets the threshold β as the shutdown threshold. InS108, the ECU 300 stops the operation of the engine 160 or prohibits theengine 160 from operating. In S110, the ECU 300 sets the threshold α asthe shutdown threshold.

In S112, the ECU 300 determines whether or not the SOC of the storageapparatus 110 is smaller than the EV threshold. When it is determinedthat the SOC of the storage apparatus 110 is smaller than the EVthreshold (YES in S112), the processing advances to S114. Otherwise (NOin S112), the processing advances to S116.

In S114, the ECU 300 operates the engine 160. When the engine 160 isoperative, the ECU 300 maintains the operation.

In S116, the ECU 300 determines whether or not the SOC of the storageapparatus 110 has fallen to or below the shutdown threshold. When it isdetermined that the SOC of the storage apparatus 110 has fallen to orbelow the shutdown threshold (YES in S116), the processing advances toS120. Otherwise (NO in S116), the processing advances to S118.

In S118, the ECU 300 determines whether or not the duration of the powersupply stoppage exceeds the second time. When it is determined that theduration of the power supply stoppage exceeds the second time (YES inS118), the processing advances to S120. Otherwise (NO in S118), theprocessing returns to S100.

In S120, the ECU 300 executes the system shutdown processing. The systemshutdown processing was described above, and therefore detaileddescription thereof will not be repeated.

An operation of the ECU 300 installed in the vehicle according to thisembodiment, based on the above structure and flowchart, will now bedescribed.

For example, when the power supply connector 600 is attached to theinlet 220 of the vehicle 100 and the plug 710 of the electric device 700is connected to the power supply connector 600, the power supplyoperation is performed in the vehicle 100 (YES in S100).

More specifically, the CHR 210 is switched ON (to a conductivecondition) such that the DC power of the storage apparatus 110 isconverted into AC power by the power conversion apparatus 200, and theconverted AC power is supplied to the electric device 700 via the inlet220, the power supply connector 600, and the plug 710.

When the electric device 700 is temporarily stopped during anintermittent operation or the like such that the power supply is stopped(YES in S102) and the duration of the power supply stoppage exceeds thefirst time (YES in S104), the threshold β is set as the shutdownthreshold (S106) and the operation of the engine 160 is stopped or theengine 160 is prohibited from operating (S108).

Hence, when the engine 160 is operative, the engine 160 is stopped, andwhen the engine 160 is stopped, the engine 160 is prohibited fromoperating. The operation of the engine 160 is likewise suppressed when,for example, the catalyst temperature falls below the activationtemperature while the engine 160 is stopped.

When the SOC of the storage apparatus 110 falls to or below the shutdownthreshold (here, the threshold β) due to power consumption by theelectric device 700 (YES in S116), the system shutdown processing isexecuted (S120), whereby the CHR 210 is switched OFF (to a shutdowncondition).

In a case where the duration of the power supply stoppage exceeds thesecond time (S118), the system shutdown processing is executed (S120)even when the SOC of the storage apparatus 110 is larger than theshutdown threshold (NO in S116).

When the power supply is not stopped (NO in S102) or the power supply isstopped (YES in S102) but the duration of the power supply stoppage doesnot exceed the first time (NO in S104), on the other hand, the thresholdα is set as the shutdown threshold (S110).

In this case, the engine 160 is operated (S114) when the SOC of thestorage apparatus 110 is smaller than the EV threshold (YES in S112).

When the SOC of the storage apparatus 110 falls to or below the shutdownthreshold (here, the threshold α) (YES in S116), the system shutdownprocessing is executed (S120), whereby the CHR 210 is switched OFF (tothe shutdown condition).

In a case where the duration of the power supply stoppage exceeds thesecond time (S118), the system shutdown processing is executed (S120)even when the SOC of the storage apparatus 110 is larger than theshutdown threshold (NO in S116).

With the vehicle according to this embodiment, as described above, whenthe power supply remains smaller than the predetermined valuecontinuously for more than the first time during the power supplyoperation for supplying power from the vehicle 100 to the power supplysubject, the operation of the engine 160 is stopped or the engine 160 isprohibited from operating. Accordingly, the engine 160 is not operatedeven when an operation of the engine 160 is requested due to a reductionin the catalyst temperature or the like in a case where the electricdevice 700 is temporarily stopped during an intermittent power supplyoperation or the like. As a result, wasteful fuel consumption can beavoided. Furthermore, a wasteful operation of the engine 160 can beavoided, and therefore an increase in exhaust gas emissions into the airaround the vehicle can be suppressed. It is therefore possible toprovide a vehicle and a control method for the vehicle with which theengine is controlled appropriately in accordance with the operatingconditions of the power supply destination.

Moreover, when the power supply is stopped, power is consumed only bythe accessories of the vehicle 100 and by switching loss and the likeoccurring in the power generation apparatus, and therefore the powerconsumption is suppressed. Stand-by is therefore possible for a longtime until an operation of the electric device 700 is resumed using thestorage apparatus 110 alone without stopping the system of the vehicle100 that is operated during the power supply operation.

Further, when the duration of the power supply stoppage exceeds thesecond time, the system of the vehicle 100 that is activated during thepower supply operation is stopped, whereby a reduction in the SOC can besuppressed. As a result, a situation in which the power supply mode isselected and then left so that the vehicle 100 cannot perform EV travelsubsequently due to a reduction in the SOC can be avoided.

The embodiments disclosed herein are entirely exemplary, and are notintended to be limiting. The scope of the invention is defined by theclaims rather than the above description, and includes all modificationsequivalent in meaning to the claims and within the scope thereof.

The invention claimed is:
 1. A vehicle comprising: an engine; an auxiliary system; a storage apparatus capable of supplying power to a power supply subject outside the vehicle; a power generation apparatus configure to supply power to the power supply subject using the engine as a power source; and an electronic control unit configured to operate the engine during a power supply operation in which power is supplied to the power supply subject from at least one of the power generation apparatus and the storage apparatus, the electronic control unit being configured to stop the engine when a duration of time in which a power supply is smaller than a predetermined value exceeds a first time, and the power supply being the power supplied to the power supply subject during the power supply operation, and the electronic control unit being configured to stop the auxiliary system of the vehicle that is activated during the power supply operation when the duration of time exceeds a second time, and the second time being longer than the first time.
 2. The vehicle according to claim 1, wherein the electronic control unit is configured to stop the operation of the engine or prohibit the engine from operating when the duration exceeds the first time.
 3. The vehicle according to claim 2, wherein the electronic control unit is configured to permit the engine to operate when the power supply is equal to or larger than the predetermined value or when the duration is equal to or shorter than the first time.
 4. The vehicle according to claim 3, wherein, in a case where the power supply is equal to or larger than the predetermined value or a case where the duration is equal to or shorter than the first time, the electronic control unit is configured to permit the engine to operate when a remaining capacity of the storage apparatus falls below a threshold.
 5. The vehicle according to claim 3, wherein, in a case where the power supply is equal to or larger than the predetermined value or a case where the duration is equal to or shorter than the first time, the electronic control unit is configured to permit the engine to operate when a catalyst temperature of the engine falls below a threshold.
 6. A control method for a vehicle including an engine, an auxiliary system, a storage apparatus, a power generation apparatus, and an electronic control unit, the control method comprising: operating, by the electronic control unit, the engine during a power supply operation in which power is supplied to a power supply subject outside the vehicle from at least one of the power generation apparatus and the storage apparatus, the power generation apparatus supplying power to the power supply subject using the engine as a power source, and the storage apparatus supplying power to the power supply subject, stopping, by the electronic control unit, an operation of the engine when a duration of time in which a power supply is smaller than a predetermined value exceeds a first time, the power supply being the power supplied to the power supply subject during the power supply operation; and stopping, by the electronic control unit, the auxiliary system of the vehicle that is activated during the power supply operation when the duration of time exceeds a second time, wherein the second time is longer than the first time. 